CLONING OF RAT 92-KDA TYPE-IV COLLAGENASE AND EXPRESSION OF AN ACTIVERECOMBINANT CATALYTIC DOMAIN

A full-length cDNA for rat 92-kDa type IV collagenase was isolated and sequenced. RNase protection assay revealed tissue specific differenti al expression of the 92-kDa type IV collagenase in the rat during deve lopment. Natural and modified forms of the 92-kDa type IV collagenase were expressed. One active protein, 92-CD, contained only the putative catalytic domain. Large quantities of the 92-CD were expressed in Esc herichia coli, extracted from inclusion bodies, purified, and refolded to an active form. This recombinant protein was able to cleave denatu red and native collagen and was inactivated by known MMP inhibitors.